Method of producing bronze-printings.



CARL A; R. LUDEWIG', OF HAMBURG, GERMANY.

METHOD OF PROliJUClNG BRONZE-PRINTIN G S.

Specification of Letters Patent.

Patented March 12, 1907.

Application filed November 13, 1905. Serial No. 287,171.

To all whom it may concern:

Be itknown that I, CARLA. R. LUDEWIG,

' a subject of the German Emperor, residing at Hamburg, Germanuhave invented a certain new and useful Method of Producing Bronze-Printings, of which the following is a specification. v

Th's invention relates to a method of producing bronze-printings,and has for its object to give printings a k-like and glittering appearance.

According to my invention bronze-printings are produced which while having the appearance of being granulated are not, but have a smootheven surface, this being due to the separation of the particles of bronze adhering to the rinted surfacef In doing this 1 mix with t e powdered bronze a soluble powdered carrier which in its dry state is not transparent, such as powdered starch, gum-arabic, glue, gelatin, or any indifferent material, preferably such as is receptive of a color when it is desired to color such carrier.

When the bronze-powder mixed with the carrier is applied to surface, preferably, but not necessarily, a colored surface that has been damped with a solvent of the car'- rier, such as water, the white powdered carrier becomes transparent and the .bronze particles are separated from one another,

.giving the silky granulated ap earance and at the same time ermitting te ground of the paper to show t rough. Y

In preparing the colored carrier it is advisable that the colors be mixed in a heated state with the carrier and preferably dissolved therein to a thick paste, which when cold is dried and ground to a fine powder. To this powder is added the bronze-powder,- the quantity of bronze-powder added varying-according to the intensity of the glittering effect. it is desired to produce, thus varying the distance apart or interstices between the bronze particles and controlling the glittering silk-like effect.

Themixture is appliedto a colored or noncolored surface by blowing it or sifting it on the surface or throwing it onthe surface while in a dam condition. When dry, the surface is brus ed to remove any surplus material or loose particles. Thus the colored cairier is rendered transparent, the color in the carrier ordinarily not being sufficient to prevent the ground of the surface" from showing through, while the particles of bronze-powder are held maintained separate to give the silk-like granular appearance, the color in .the transparent carrier thus modifying the color of the ground. When the 'bronze-powder'is mixed with the uncolored carrier, the surfaces are usually printed or otherwise provided with color, and while they are still in a damp state the, mixture of bronze-powder and carrier is applied in the manner stated above. This mode of carrying the method into effect has the advantage that no previous or first impression is neces-.

sary, since the same is replaced by the real color-print, and that the colored bronzeprints thus obtained will resist washing off with water. For this reason not only pa er or the like can be printed according to t is invention, but also leather or fabric of any description, such as cloth, linen, silk, calico, &c. Fabrics treated in this manner may be used for book-coverings, ladies dresses, wall decorations, and the like.

1 claim- 1. The method of producing bronze-printings having a lustrous, silk-like appearance,

which comprises producing a 'mixture of powdefed bronze and a soluble powdered carrier capable of being rendered transparent by a suitable solvent, damping a surface with said solvent and applying the mixture thereto to permit the ground of said surface to show through the carrier thus rendered transparent, said bronze particles maintained separated by the carrier. 2. The method of producing bronze-printings having a lustroussilk-like appearance, which comprises producing a mixture of powdered bronze and a soluble powdered colored carrier capable of being rendered transparent by a suitable solvent, damping a colored surface with said solvent and applying the mixture thereto to permit the color to show through the carrier thus rendered transparent, said bronze particle's maintained separated by the carrier.

, CARL A. R. LUDEWIG. lVitnesses:

HARRY RAEGKNER, IDA CHRIST. HAFERMANN. 

